According to John Dean, it's possible.

John Dean knows something about White House abuse of power. He wrote a bestseller in 2004 on the Bush White House called Worse Than Watergate. In a recent interview I asked him what he thinks of that title now. Now, he replied, a book comparing Bush and Nixon would have to be called Much, Much Worse.

"Look at the so-called Watergate abuses of power," he said. "Nobody died. Nobody was tortured. Millions of Americans were not subject to electronic surveillance of their communications. We're playing now in a whole different league."

And how does Bush compare with the Republicans seeking to succeed him? "If a Rudy Giuliani were to be elected," Dean said, "he would go even farther than Cheney and Bush in their worst moments."